There's a big difference between the Ruger 45/22 and S&W 686's sights. One is a 22 caliber target pistol and the other is basically a service/duty gun. The target sights on the Ruger allow for a more precision shot whereas the 686 is more of a "center of mass" sight picture. You can change the front sight on the 686 but honestly I think the sights that come with it are fine. I use my 4" 686 for bowling pin matches where the pins are set up at 20 yards. better yet, we cut the top 6" off the pins and set up 3 pin bodies and two pin tops. I can hit a 6" x 2" pin head with my factory sights. Took lots of practice though.

You can also I believe change the rear sight for a wider notch. I might be wrong on that but I believe S&W offers different width rear sights. You can find them on MidwayUSA or Brownells.